Larry Kruzan on mon 20 sep 10
If there is any other information about this sort of issue, I'd sure like t=
o
know of it. I own 5 of the 28" Corelite full round shelves that have been
fired to cone 8, 5 times with no problem. I also three post my shelves -
seems like a big shelf for three posts but that is the recommended method.
These are a major investment for me and I care for them like they were my
firstborn. If Jack Troy could have problems, it sure concerns little ole me=
.
Larry Kruzan
Lost Creek Pottery
www.lostcreekpottery.com
-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of Donovan
Palmquist
Sent: Monday, September 20, 2010 5:55 PM
To: Clayart@LSV.CERAMICS.ORG
Subject: corelite kiln shelves
I am posting this for Jack Troy:
Hello Julie and Graham (at Standard Ceramics),
I was shocked this morning when I unloaded my bisque kiln to find that 4 ou=
t
of 5 of my nearly-new 22" round Core-Lite shelves (only a dozen firings on
them) had broken almost precisely in half. The kiln was loaded with plates
16-
18" across, one per shelf. None was what I'd call "heavy" - they were foote=
d
in the manner of dinner plates. The firing temp was c/012. I used 3-point
supports and the cracking was not at all consistent from one shelf to the
next,
and was irrespective of where the supports were located. The cracking was,
however, consistent in that it occurred parallel with the cores; not across
them.
I have never "crash-cooled" my kiln - an L&L - nor taken it up quickly. I
use
only the "slow bisque" or "fast bisque" cycle, and usually preheat for a
couple
of hours.
In this case, I set it on slow bisque with a 2-hour pre-heat, then came bac=
k
in
5 hours, when it was about 250F. I shut the kiln off and re-set it for a
fast
bisque cycle for the remainder of the firing which took about 7 hours.
I cracked the lid at 250, left it over-night, and unloaded this morning. Th=
e
plates were fine, but my shelves! This is more than discouraging, to say th=
e
least!
Have you ever heard of such a thing? I'm pretty heavily invested in those
shelves; fortunately I have a few left from my order and plan to use them,
but
I naturally will have very little confidence in their longevity.
Thanks for hearing me out.
Jack Troy
=3D=3D=3D=3D=3D=3D=3D
Email scanned by PC Tools - No viruses or spyware found.
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Donovan Palmquist on mon 20 sep 10
I am posting this for Jack Troy:
Hello Julie and Graham (at Standard Ceramics),
I was shocked this morning when I unloaded my bisque kiln to find that 4 =
=3D
out=3D20
of 5 of my nearly-new 22" round Core-Lite shelves (only a dozen firings o=
=3D
n=3D20
them) had broken almost precisely in half. The kiln was loaded with plate=
=3D
s 16-
18" across, one per shelf. None was what I'd call "heavy" - they were foo=
=3D
ted=3D20
in the manner of dinner plates. The firing temp was c/012. I used 3-point=
=3D
=3D20
supports and the cracking was not at all consistent from one shelf to the=
=3D
next,=3D20
and was irrespective of where the supports were located. The cracking was=
=3D
,=3D20
however, consistent in that it occurred parallel with the cores; not acro=
=3D
ss=3D20
them.
I have never "crash-cooled" my kiln - an L&L - nor taken it up quickl=3D
y. I use=3D20
only the "slow bisque" or "fast bisque" cycle, and usually preheat for a =
=3D
couple=3D20
of hours.
In this case, I set it on slow bisque with a 2-hour pre-heat, then came b=
=3D
ack in=3D20
5 hours, when it was about 250F. I shut the kiln off and re-set it for a =
=3D
fast=3D20
bisque cycle for the remainder of the firing which took about 7 hours.
I cracked the lid at 250, left it over-night, and unloaded this morning. =
=3D
The=3D20
plates were fine, but my shelves! This is more than discouraging, to say =
=3D
the=3D20
least!
Have you ever heard of such a thing? I'm pretty heavily invested in those=
=3D
=3D20
shelves; fortunately I have a few left from my order and plan to use them=
=3D
, but=3D20
I naturally will have very little confidence in their longevity.
Thanks for hearing me out.
Jack Troy
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